History of HubBackend::block 2 changes

In crates/hub/src/protocol.rs, lines 45–47 on bf1ab3458db1c2cfdacecf34f981ef54baa28f8d6a453cc7b24bd2c53530a904. Every change that wrote or deleted one of these lines, or deleted a line from between them. Exact, because each line keeps its identity across edits; edits elsewhere in the file are not here. Also: oxy log -L 45,47:crates/hub/src/protocol.rs.